Will the insanity NEVER end?!

[Patrick82]

Quote:

Originally Posted by Sinbios Well, could you pull out some evidence where the CD drive actually "recreates" the audio stream, instead of just passing the bits to the DAC?

You're still not reading it correctly. The CD drive doesn't recreate the audio stream, it passes on the 0s and 1s at certain intervals (time) to the DAC, the DAC creates the audio stream based on data + timing. But if the data doesn't reach the DAC in a linear fashion you will get jitter!

It's the timing that is analog, and it can get interfered by many things before it reaches the DAC.

 

[Sinbios]

Quote:

Originally Posted by Patrick82 You're still not reading it correctly. The CD drive doesn't recreate the audio stream, it passes on the 0s and 1s at certain intervals (time) to the DAC, the DAC creates the audio stream based on data + timing. But if the data doesn't reach the DAC in a linear fashion you will get jitter! It's the timing that is analog, and it can get interfered by many things before it reaches the DAC.

But the article clear states, and I quote again, "For one of these two waveform dimensions, the vertical amplitude axis, the CD contains some information, but the data coming from the CD are emphatically not fully or adequately descriptive of the music waveform's ever changing amplitude, especially for musical frequencies above 2 kHz or so." So it's arguing that amplitude is incorrectly represented by the CD. It also states "In truth, the CD playback unit is actually responsible for literally freshly creating the entire two dimensional music waveform, which it then outputs to the rest of your system," which I take to mean that the author is implying that the CD drive is recreating the music stream.

Ooh, ooh. Here's another flaw, in the introduction section:

Quote:

Because the mere fact that the sound of a CD could be changed meant that bits were in point of fact not bits, and therefore that the CD medium was necessarily imperfect and furthermore was subject to the whims of motley external factors

So his logic is that: Someone subjectively perceived the sound of a CD to change when tweaked -> bits are not really bits! (Gee, what are they, then?) -> The CD medium, i.e. the digital format, is necessarily imperfect!

This is the kind of flawed logic I gave some examples to earlier on. The reason the reasoning is flawed is because he derives these findings through his "logic" and presents them as facts with the words "in point of fact", "necessarily", etc, while these derivations are based on an event that may or may not have even physically occured!

 

[bigshot]

Quote:

Originally Posted by Sinbios The CD is an EXACT replica of the bits that has been passed to it, and will give it back exactly the same way; the author of that article describes a process where you give a chunk of music to the CD, the CD decides what to keep and what not to keep, and gives you back part of the music. This happens in tapes, not CDs.

That would be an interesting topic for discussion. I've noticed the similarity between comments about CDs and those folks used to have about analogue recordings too. The difference is, everyone could hear analogue generation loss. There was a reason to be anal retentive.

See ya
Steve

 

[Patrick82]

Quote:

Originally Posted by Sinbios It also states "In truth, the CD playback unit is actually responsible for literally freshly creating the entire two dimensional music waveform, which it then outputs to the rest of your system," which I take to mean that the author is implying that the CD drive is recreating the music stream.

The 2 dimensional waveform is data+time.

 

[JaZZ]

Quote:

Originally Posted by Sinbios He said that the information concerning amplitude coming from the CD is not sufficient! To be precise, he said "For one of these two waveform dimensions, the vertical amplitude axis, the CD contains some information, but the data coming from the CD are emphatically not fully or adequately descriptive of the music waveform's ever changing amplitude, especially for musical frequencies above 2 kHz or so." As if the CD or CD writer could decide that, "Ah! A music file is being put on me! Better choose to ignore some of the bits that pertain to the amplitude axis! Aha, here's some audio signal above 2 kHz! Better discard some more of this!" The only place this might happen is when converting from digital to analogue or vice versa, and neither of these processes happen at the CD or CD drive. The CD is an EXACT replica of the bits that has been passed to it, and will give it back exactly the same way; the author of that article describes a process where you give a chunk of music to the CD, the CD decides what to keep and what not to keep, and gives you back part of the music.

No. He doesn't say the CD «decides what to keep and what not to keep», but that the data on the CD are not sufficient to describe the waveform. This especially applies to frequencies above 2 kHz. And he's absolutely right about this. For the record: With usual DACs none of the amplitude values on the CD is preserved in the final analog signal: It's the filter algorithm of the antialiasing filter which decides on it. Because the unfiltered signal looks like this -- demonstrated on sine waves (from http://www.mother-of-tone.com/cd.htm):

Without a steep low-pass filter you get a strange amplitude modulation (which is not the classic aliasing from frequencies above the Nyquist limit!). For eliminating it you have to introduce the filter ringing (Gibbs phenomenon), with its time-smearing effect. So depending on the filter characteristic and the filter algorithm used for interpolating between the samples you get different waveforms. But one thing they'll have in common: None of the original amplitude values stored on the CD is preserved in them.


Quote:

Well, could you pull out some evidence where the CD drive actually "recreates" the audio stream, instead of just passing the bits to the DAC?

«Passing the bits to the DAC» is not the correct description of the process. The laser pickup has to read the code, which results in a certain analog waveform, which now the DAC has to interpret. This waveform again will vary from transport to transport and even from CD to CD. That's where the time domain -- and thus jitter -- comes into play.


Quote:

But the article clear states, and I quote again, "For one of these two waveform dimensions, the vertical amplitude axis, the CD contains some information, but the data coming from the CD are emphatically not fully or adequately descriptive of the music waveform's ever changing amplitude, especially for musical frequencies above 2 kHz or so." So it's arguing that amplitude is incorrectly represented by the CD. It also states "In truth, the CD playback unit is actually responsible for literally freshly creating the entire two dimensional music waveform, which it then outputs to the rest of your system," which I take to mean that the author is implying that the CD drive is recreating the music stream.

See above.


Quote:

Ooh, ooh. Here's another flaw, in the introduction section: Quote: Because the mere fact that the sound of a CD could be changed meant that bits were in point of fact not bits, and therefore that the CD medium was necessarily imperfect and furthermore was subject to the whims of motley external factors So his logic is that: Someone subjectively perceived the sound of a CD to change when tweaked -> bits are not really bits! (Gee, what are they, then?) -> The CD medium, i.e. the digital format, is necessarily imperfect!

Yes, exactly! Because what we hear is decisive, isn't it? And even you will probably concede that the hi-rez formats sound better than redbook CD, no? There's enough theoretical evidence that 16 bit and particularly 44.1 kHz are not the last word in terms of signal accuracy -- and not enough for sensitive hearings.


Quote:

This is the kind of flawed logic I gave some examples to earlier on. The reason the reasoning is flawed is because he derives these findings through his "logic" and presents them as facts with the words "in point of fact", "necessarily", etc, while these derivations are based on an event that may or may not have even physically occurred!

In other words: His fault is to hear something you can't hear? After all he's not alone!

 

[bigshot]

I wonder if we could create a forum where "If you can't hear the difference there is something wrong with your ears or your equipment." is forbidden. What would we call that? No FE&/orE (Faulty Ears &/or Equipment)?

See ya
Steve

 

[JaZZ]

Quote:

Originally Posted by bigshot I wonder if we could create a forum where "If you can't hear the difference there is something wrong with your ears or your equipment." is forbidden.

There's nothing wrong with your ears if you don't hear something someone else hears -- everybody's hearing is different. But there's not automatically something wrong with something somebody hears if someone else doesn't hear it. This because of the first scenario and also because resolution varies a lot between different systems. (And e.g. there's more to audio than a linear frequency response.

)

 

[K2Grey]

OK, let me continue stuff with a question.

What determines the timing of the passing of the 0/1 information? Is there a constant timing which is to be followed (in which case timing it correctly seems trivial to me), or does the amount of time between each bit vary for some reason (in which case where is the information for the timing stored?)

 

[Publius]

I'm going to avoid getting into this debate for as long as possible, but I will throw this out.

I have an EE degree. I have some training (not as much as many people on head-fi) in analog and digital design. I know for certain - and every prof worth his salt will back me up on this - that all digital signals are analog. Zeroes and ones are only approximated by analog values with known distortions like ringing/overshoots, rise/fall times and the like. Similarly discrete time values are only approximated and things like jitter and clock skew can creep in.

That said, I'll repeat what I've said a million times before: it's one thing to sprout off all the theoretical ways that a circuit can distort and how you can fix it, but it's something much more difficult to actually prove beyond the shadow of a doubt that those distortions (or fixes) are in fact audible. Even if they show up clearly on a scope.

I will assert without further discussion that GS has not given this proof.

 

[Penten]

Music, in my opinion, is music because it's imperfect. If you want perfection then buy yourself an oscillator and save a lot of money.

Secondly, I'm not saying that any of these tweaks work or not, but when someone spends $5000 on something their brain is going to be pretty reluctant to think that it was a mistake.

 

[geek707]

Quote:

Originally Posted by markl I love how some of the self-described "objectivists" often like to whine about how they aren't allowed to whine about subjective impressions on this forum. Many of them seem to have severe persecution complexes. Have you read your own posts in this thread? from another perspective, all I see nowadays in the cables forum is constant sniping from the objectivist crowd, and certainly I don't see anything being done about it, despite my attempts to bring all that to the Mods attention last month. Has a mod come in and removed any of your comments? I didn't think so. It seems one is free to continue to make DBT-style arguments, ridicule subjective impressions, and be generally rude to one's heart's desire without incurring any warnings, cautions, or slaps on the wrist, so long as the actual keys typed in succession do not spell D-B-T. You see objectivists being persecuted, other people see them running rough-shod and being rude and condescending at every turn. Maybe if that's the case, the Mods feel Head-Fi must be working correctly.

Defensive>Check
Rude>Check
Whining about someone else being rude>Check
Whining about the Mods>Check
Mark you should really look in a mirror sometime...